I'm working on a class project where we make a pie chart out of an attribute table. The attributes are geologic layers (UNITNAME), and the area they occupy (area_pct). In the "Create Graph Wizard", I have selected the correct table, and set the value field to "area_pct" and the label field to "UNITNAME". However, I can't get the sort field to let me select anything. I want the sort field to be "UNITNAME" as well. I managed to get it to work yesterday by goofing around with the options, but I honestly have no idea how I did it, and now I can't replicate it.
Does anyone have any suggestions? Is this arcGIS (10.2.1) just being picky as usual?